A supplement best known for helping athletes build strength may also help the immune system fight cancer, according to a new study. Researchers found that creatine, a naturally occurring compound widely used as a fitness supplement, can strengthen key immune cells that detect tumours and activate the body’s cancer-fighting response.

The findings suggest creatine could one day become an inexpensive addition to cancer immunotherapy, although the research is still at an early stage and has so far been tested mainly in mice.

How creatine helps the immune system fight cancer

The study focused on dendritic cells (DCs), often described as the “sentinels” of the immune system. These cells detect abnormal or cancerous cells, process their markers (antigens), and present them to CD8 T cells—the immune cells that directly kill cancer cells.

Researchers noted that dendritic cells are “central regulators of antitumor T cell immunity” but that the possibility of improving their function by altering their metabolism has received relatively little attention.

The team discovered that dendritic cells inside tumours had unusually high levels of a protein called the creatine transporter (CrT or Slc6a8), which allows the cells to absorb creatine from their surroundings.

To understand why this mattered, researchers studied mice that lacked this transporter. Without it, dendritic cells were less active and much less effective at stimulating CD8 T cells, weakening the immune response against tumours.

The opposite was also true. When mice with normal creatine transporters received creatine supplements, their dendritic cells became more active and tumour growth slowed in a mouse model of melanoma.

Importantly, the researchers observed a similar effect in human immune cells grown in the laboratory. Human dendritic cells exposed to creatine also became more active and better at stimulating cancer-fighting immune responses.

Creatine gives immune cells the energy they need

The researchers found that creatine worked by helping dendritic cells maintain their energy supply.

Cells rely on a molecule called ATP (adenosine triphosphate) as their primary source of energy. Activating the immune system is an energy-intensive process, requiring cells to grow, communicate and release inflammatory signals.

The study found that creatine acts as an energy reserve, helping preserve ATP levels inside dendritic cells. This allowed them to maintain the energy needed to activate inflammatory signalling pathways and efficiently alert CD8 T cells to the presence of tumours.

Based on these findings, the researchers proposed what they called a “creatine-uptake/energy-buffering” model. According to this model, when dendritic cells encounter signs of tumour damage, they increase their uptake of creatine. The stored creatine then helps maintain ATP levels, keeping the cells energised and improving their ability to activate cancer-killing T cells.

What happened in mice?

The benefits extended beyond changes inside individual cells.

In mice with melanoma, creatine supplementation significantly slowed tumour growth and increased both the number and activity of a specialised type of dendritic cell known as conventional dendritic cells type 1 (cDC1s), which are particularly effective at initiating anti-cancer immune responses.

The treated mice also showed stronger CD8 T-cell responses against tumours.

Experiments using human dendritic cells produced similar encouraging results. Creatine-treated cells became better at presenting tumour markers to CD8 T cells, making it easier for these immune cells to recognise and attack cancer cells.

The researchers also found that creatine increased the production of chemical signals that attract both CD8 T cells and natural killer (NK) cells into tumours, potentially strengthening the overall immune attack.

What could this mean for cancer treatment?

The findings may have implications for cancer immunotherapy.

Current immune checkpoint blockade (ICB) treatments mainly work by reactivating exhausted T cells. However, these therapies are often less effective in so-called “cold” tumours, which contain very few immune cells to begin with.

By boosting dendritic cells instead, creatine supplementation could potentially help make these tumours more visible to the immune system, providing what the researchers described as an “economical, mechanistically nonredundant co-therapy strategy.”

The researchers also noted that low blood creatine levels are often seen in people with advanced cancer, particularly those with cachexia—a severe wasting syndrome marked by muscle and weight loss. Previous studies have suggested creatine supplementation may help reduce muscle wasting and protect against some chemotherapy-related heart damage, although those benefits were not the focus of the current research.

The findings are promising, but more research is needed

The researchers cautioned that the relationship between creatine and cancer is complex.

While this study showed that creatine strengthened anti-tumour immune responses, previous research has suggested that some cancer cells can also use creatine to support their own growth and spread. However, those studies did not examine creatine’s effects on the immune system, which was the focus of the current research.

The team said more studies are needed to understand how creatine affects different cell types within tumours and to determine whether the benefits seen in mice can be replicated in people.

They also pointed to evidence from the US National Health and Nutrition Examination Survey, which found that people with higher dietary creatine intake had lower rates of cancer. Combined with creatine’s long history of safe use as a dietary supplement, the researchers believe these findings support testing creatine as an addition to future cancer immunotherapy trials.

The study also suggested that creatine could improve dendritic cell-based cancer vaccines, another form of immunotherapy currently being explored.

For now, the findings offer an intriguing new perspective on a familiar supplement—but experts emphasise that people should not take creatine as a cancer treatment outside clinical research until its benefits are confirmed in human trials.

This story is done in collaboration with First Check, the health journalism vertical of DataLEADS. 

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